Scientists at the University of Western Ontario, Canada, discovered the components of fruit juices inhibit the absorption of drugs into the blood. So far, it has been known only about bergamottin in grapefruit juice that reduces the activity of ferment responsible for breaking down drugs in the bowels.
New study shows that naringin (substance that gives the bitter taste to grapefruit) blocks OATP1A2 protein that transports drugs from small intestine to the blood. On the other hand, if you wash your pill down with water, it will be half-absorbed into the blood. The ability to block the protein transporter has been also discovered in apple and orange juices. That’s why, scientists advice that you wash down your drugs strictly with water.